They seem to be implying that the different tiers of Roomba robots are differentiated by how much square footage they can clean in a session, not that Roomba literally has a usage based pricing model. I don’t know how they came to that conclusion though.

I wasn't aware of this either (if it's not a joke)... if so, it would be right up there with HP printers refusing to scan if you don't buy ink.

GP is incorrect. Roomba does not charge by sqft

I own two Roombas and have never heard of this.

Not yet, but this is the future. After all, people don't want vacuum cleaners, they want clean apartments, cleaning is a service, and other such self-aggrandizing business bullshit. Welcome to the future!